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Networks of optical clocks find applications in precise navigation1,2, in efforts to redefine the fundamental unit of the 'second'3-6 and in gravitational tests7. As the frequency instability for state-of-the-art optical clocks has reached the 10-19 level8,9, the vision of a global-scale optical network that achieves comparable performances requires the dissemination of time and frequency over a long-distance free-space link with a similar instability of 10-19. However, previous attempts at free-space dissemination of time and frequency at high precision did not extend beyond dozens of kilometres10,11. Here we report time-frequency dissemination with an offset of 6.3 × 10-20 ± 3.4 × 10-19 and an instability of less than 4 × 10-19 at 10,000 s through a free-space link of 113 km. Key technologies essential to this achievement include the deployment of high-power frequency combs, high-stability and high-efficiency optical transceiver systems and efficient linear optical sampling. We observe that the stability we have reached is retained for channel losses up to 89 dB. The technique we report can not only be directly used in ground-based applications, but could also lay the groundwork for future satellite time-frequency dissemination.
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BACKGROUND: Human papillomavirus (HPV) infection is an important factor leading to cervical cell abnormalities. 90% of cervical cancers are closely associated with persistent infection of high-risk HPV, with the highest correlation with HPV16 and 18. Currently available vaccines and antivirals have limited effectiveness and coverage. Guanylate binding protein 1 (GBP1) was induced by interferon gamma and involved in many important cellular processes such as clearance of various microbial pathogens. However, whether GBP1 can inhibit human papillomavirus infection is unclear. RESULTS: In this study, we found that GBP1 can effectively degrade HPV18 E6, possibly through its GTPase activity or other pathways, and E6 protein degrades GBP1 through the ubiquitin-proteasome pathway to achieve immune escape. CONCLUSION: Therefore, GBP1 is an effector of IFN-γ anti-HPV activity. Our findings provided new insights into the treatment of HPV 18 infections.
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Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Proteínas de Ligação ao GTP , Papillomavirus Humano 18 , Interferon gama/farmacologiaRESUMO
In this work, boron and nitrogen-codoped carbon dots (BN-CDs) as highly efficient electrochemiluminescence (ECL) emitters with advantages of low excitation potential and high ECL efficiency were prepared to establish a novel ternary ECL system for ultrasensitive detection of HBV-DNA. Especially, both platinum nanoflowers (Pt NFs) and boron radicals (Bâ¢) from the BN-CDs could accelerate the reduction of coreactant S2O82- to abundant SO4â¢- simultaneously, making the BN-CDs have outstanding ECL performance. Impressively, the ECL efficiency of BN-CDs is much higher than that of nondoped CDs and single-doped CDs. In addition, by combining the novel ECL ternary system with the exonuclease III (Exo III)-induced target DNA amplification strategy, an ECL biosensor was constructed to realize the ultrasensitive detection of HBV-DNA from 100 aM to 1 nM, while the limit of detection was 18.08 aM. Therefore, a promising highly efficient ECL emitter was offered to develop a novel ECL detection method for clinical disease analysis.
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Técnicas Biossensoriais , MicroRNAs , Pontos Quânticos , Técnicas Biossensoriais/métodos , Boro , Carbono , DNA Viral/genética , Técnicas Eletroquímicas/métodos , Vírus da Hepatite B/genética , Limite de Detecção , Medições Luminescentes/métodos , MicroRNAs/análise , NitrogênioRESUMO
Herein, we designed a dual 3D DNA nanomachine (DDNM)-mediated catalytic hairpin assembly (DDNM-CHA) to construct an electrochemical biosensor for ultrasensitive detection of miRNA, which possesses quite a faster reaction rate and much higher amplification efficiency than those of traditional catalytic hairpin assembly (CHA). Impressively, since the DDNM skillfully increases the local concentration of reactants and decreases the steric hindrance of substrates simultaneously, the DDNM-CHA could be endowed with higher collision efficiency and more effective reaction compared with traditional CHA, resulting in a hyper conversion efficiency up to 2.78 × 107 only in 25 min. This way, the developed DDNM-CHA could easily conquer the main predicaments: long reaction time and low efficiency. As a proof of the concept, we adopt the gold nanoparticles (AuNPs) and the magnetic nanoparticle (Fe3O4) as the kernel of DNM-A and DNM-B, respectively, and harness the magnetic electrode to directly adsorb the products H1-H2/Fe3O4 for constructing an immobilization-free biosensor for high-speed and ultrasensitive detection of miRNA with a detection limit of 0.14 fM. As a result, the DDNM-CHA we developed carves out a new insight to design a functional DNA nanomachine and evolve the analysis method for practical amplification in the sensing area and promotes the deeper exploration of the nucleic acid signal amplification strategy and DNA nanobiotechnology.
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Técnicas Biossensoriais , DNA Catalítico , Nanopartículas Metálicas , MicroRNAs , DNA , Técnicas Eletroquímicas , Ouro , Limite de DetecçãoRESUMO
In this work, an original rolling-circle strand displacement amplification (RC-SDA) was developed by introducing a circle DNA with two recognition domains as a template instead of the limited liner DNA template in traditional strand displacement amplification (SDA), which displayed much shorter reaction time down to 30 min and quite higher conversion efficiency of more than 1.77 × 108 compared with those of traditional strand displacement amplification (SDA) and could be applied to construct a label-free biosensor for ultrasensitive detection of an HIV DNA fragment. Once the target HIV DNA fragment interacts with the template circle DNA, the RC-SDA could be activated to dramatically output amounts of mimic target DNA with the assistance of the Phi29 DNA polymerase and Nb.BbvCI enzyme. In application, while the output products were captured by the DNA tetrahedral nanoprobe (DTNP) modified electrode, the electrochemical tag silver nanoclusters (AgNCs) on DTNP would be released from the electrode surface, accompanied with an obviously decreased electrochemical signal. This way, the developed signal-off biosensor was successfully applied to realize the rapid and ultrasensitive detection of target HIV DNA fragment with a detection limit down to 0.21 fM, which exploits the new generation of a universal strategy beyond the traditional ones for applications in biosensing assay, clinic diagnosis, and DNA nanobiotechnology.
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Técnicas Biossensoriais , Técnicas Eletroquímicas , DNA/genética , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico , PrataRESUMO
Herein, the boron radical active sites of boron carbon oxynitride quantum dots (BCNO QDs) are electrically excited to produce boron radicals (Bâ¢) for catalyzing peroxydisulfate (S2O82-) as a coreactant to accelerate the generation of abundant sulfate radicals (SO4â¢-) for significant enhancement in the electrochemiluminescence (ECL) efficiency of BCNO QDs, which overcome the defect of traditional carbon-based QDs with low ECL efficiency. Impressively, under extremely low concentration of S2O82- solution, the BCNO QDs/S2O82- system could exhibit high ECL emission, realizing environmental friendliness and excellent biocompatibility for sensitive bioanalysis. As a proof-of-concept, BCNO QDs, a new generation of ECL emitters with high ECL efficiency, were successfully used in the ultrasensitive determination of microRNA-21, which pushes the exploration of new ECL emitters and broadens the application in the field of clinical diagnosis, ECL imaging, and molecular devices.
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Compostos de Boro/química , Limite de Detecção , Medições Luminescentes/métodos , MicroRNAs/análise , Pontos Quânticos/química , Catálise , Eletroquímica , MicroRNAs/químicaRESUMO
The booming of host-guest assembly-based supramolecular chemistry provides abundant ways to construct functional systems and materials. Attracted by the important application prospect of white light emission and aggregation-induced emission (AIE) materials, herein, we report an efficient way for fabricating metal-free white light-emitting AIE materials through the supramolecular assembly of simple organic compounds: methoxyl pillar[5]arene (MP5) and tri-(pyridine-4-ylamido)benzene (TAP). By host-guest assembly, MP5 and TAP formed a supramolecular polymer (MP5-T); meanwhile, the MP5-T xerogel powder emitted white light at CIE coordinates (0.29 and 0.29). The supramolecular assembly and white light-emitting mechanisms were carefully investigated by experiments as well as quantum chemical calculations including density functional theory (DFT), reduced density gradient, electrostatic surface potential, independent gradient model, and frontier molecular orbital (highest-occupied molecular orbital-lowest-unoccupied molecular orbital) analyses. Interestingly, according to the experiments and calculations, the supramolecular assembly is critical in the white light-emitting phenomenon. Moreover, in this work, the quantum chemical calculations could not only support experimental phenomena but also provide deep understanding and visualized presentation of the assembly and emission mechanism. In addition, the obtained MP5-T solid powder could serve as a novel and easy means to make material for white light-emitting devices.
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A group of 2-methyl-4-phenylquinoline-chalcone analogs (2a-2x) was synthesized and investigated for anti-depressant, anti-inflammatory, and analgesic effects as cyclooxygenase-2 inhibitors. Pharmacological experiments identified 24 analogs that exhibited anti-depressant, anti-inflammatory, and analgesic activities. In particular, compounds 2c, 2k, and 2w markedly shortened immobility times and exhibited the most anti-depressant activity. In addition, the mechanisms of action of the analogs 2c, 2k, and 2w were likely related to increased serotonin levels in the central nervous system. Compounds 2c, 2k, and 2w displayed reasonable cyclooxygenase-2 inhibitory effects (IC50 values from 0.21 to 0.29 µmol/L) similar to celecoxib (IC50: 0.19 µmol/L) in vitro. A molecular docking study of compound 2k also was conducted.
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Analgésicos/química , Anti-Inflamatórios/química , Antidepressivos/química , Chalcona/química , Inibidores de Ciclo-Oxigenase 2/química , Ciclo-Oxigenase 2/metabolismo , Analgésicos/metabolismo , Anti-Inflamatórios/metabolismo , Antidepressivos/metabolismo , Sítios de Ligação , Celecoxib/química , Chalcona/metabolismo , Ciclo-Oxigenase 1/química , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/metabolismo , Desenho de Fármacos , Humanos , Simulação de Acoplamento Molecular , Relação Estrutura-AtividadeRESUMO
BACKGROUND: This study aimed to investigate integrating radiomics with clinical factors in cranial computed tomography (CT) to predict ischemic strokes in patients with silent lacunar infarction (SLI). METHODS: Radiomic features were extracted from baseline cranial CT images of patients with SLI. A least absolute shrinkage and selection operator (LASSO)-Cox regression analysis was used to select significant prognostic factors based on ModelC with clinical factors, ModelR with radiomic features, and ModelCR with both factors. The Kaplan-Meier method was used to compare stroke-free survival probabilities. A nomogram and a calibration curve were used for further evaluation. RESULTS: Radiomic signature (p < 0.01), age (p = 0.09), dyslipidemia (p = 0.03), and multiple infarctions (p = 0.02) were independently associated with future ischemic strokes. ModelCR had the best accuracy with 6-, 12-, and 18-month areas under the curve of 0.84, 0.81, and 0.79 for the training cohort and 0.79, 0.88, and 0.75 for the validation cohort, respectively. Patients with a ModelCR score < 0.17 had higher probabilities of stroke-free survival. The prognostic nomogram and calibration curves of the training and validation cohorts showed acceptable discrimination and calibration capabilities (concordance index [95% confidence interval]: 0.7864 [0.70-0.86]; 0.7140 [0.59-0.83], respectively). CONCLUSIONS: Radiomic analysis based on baseline CT images may provide a novel approach for predicting future ischemic strokes in patients with SLI. Older patients and those with dyslipidemia or multiple infarctions are at higher risk for ischemic stroke and require close monitoring and intensive intervention.
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Encéfalo/diagnóstico por imagem , AVC Isquêmico/diagnóstico por imagem , Acidente Vascular Cerebral Lacunar/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nomogramas , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Análise de SobrevidaRESUMO
OBJECTIVE: To investigate the current status of antibiotic use for very and extremely low birth weight (VLBW/ELBW) infants in neonatal intensive care units (NICUs) of Hunan Province. METHODS: The use of antibiotics was investigated in multiple level 3 NICUs of Hunan Province for VLBW and ELBW infants born between January, 2017 and December, 2017. RESULTS: The clinical data of 1â442 VLBW/ELBW infants were collected from 24 NICUs in 2017. The median antibiotic use duration was 17 days (range: 0-86 days), accounting for 53.0% of the total length of hospital stay. The highest duration of antibiotic use was up to 91.4% of the total length of hospital stay, with the lowest at 14.6%. In 16 out of 24 NICUs, the antibiotic use duration was accounted for more than 50.0% of the hospitalization days. There were 113 cases with positive bacterial culture grown in blood or cerebrospinal fluid, making the positive rate of overall bacterial culture as 7.84%. The positive rate of bacterial culture in different NICUs was significantly different from 0% to 14.9%. The common isolated bacterial pathogens Klebsiella pneumoniae was 29 cases (25.7%); Escherichia coli 12 cases (10.6%); Staphylococcus aureus 3 cases (2.7%). The most commonly used antibiotics were third-generation of cephalosporins, accounting for 41.00% of the total antibiotics, followed by penicillins, accounting for 32.10%, and followed by carbapenems, accounting for 13.15%. The proportion of antibiotic use time was negatively correlated with birth weight Z-score and the change in weight Z-score between birth and hospital discharge (rs=-0.095, -0.151 respectively, P<0.01), positively correlated with death/withdrawal of care (rs=0.196, P<0.01). CONCLUSIONS: Antibiotics used for VLBW/ELBW infants in NICUs of Hunan Province are obviously prolonged in many NICUs. The proportion of routine use of third-generation of cephalosporins and carbapenems antibiotics is high among the NICUs.
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Recém-Nascido de Peso Extremamente Baixo ao Nascer , Antibacterianos , Peso ao Nascer , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Inquéritos e QuestionáriosRESUMO
Our previous study has shown heme oxygenase-1 (HO-1) protects human lens epithelial cells (LECs) against H2O2-induced oxidative stress and apoptosis. Nrf2, the major regulator of HO-1, is triggered during the mutual induction of oxidative stress and ER stress. In response to ER stress, unfolded protein response (UPR) serves as a program of transcriptional and translational regulation mechanism with PERK involved. Both Nrf2 and ATF4 are activated as the downstream effect of PERK signaling coordinating the convergence of dual stresses. However, the ways in which Nrf2 interacting with ATF4 regulates deteriorated redox state have not yet been fully explored. Here, the transfected LECs with Nrf2 overexpression illustrated enhanced resistance in morphology and viability upon H2O2 treatment condition. Intracellular ROS accumulation arouses ER stress, initiating PERK dependent UPR and inducing the downstream signal Nrf2 and ATF4 auto-phosphorylation. Further, converging at target promoters, ATF4 facilitates Nrf2 with the expression of ARE-dependent phase II antioxidant and detoxification enzymes. According to either Nrf2 or ATF4 gene modification, our data suggests a novel interaction between Nrf2 and ATF4 under oxidative and ER stress, thus drives specific enzymatic and non-enzymatic reactions of antioxidant mechanisms maintaining redox homeostasis. Therapies that restoring Nrf2 or ATF4 expression might help to postpone LECs aging and age-related cataract formation.
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Fator 4 Ativador da Transcrição/metabolismo , Estresse do Retículo Endoplasmático , Células Epiteliais/citologia , Cristalino/citologia , Fator 2 Relacionado a NF-E2/fisiologia , Estresse Oxidativo , Western Blotting , Catalase/metabolismo , Linhagem Celular , Citoproteção , Células Epiteliais/metabolismo , Citometria de Fluxo , Técnica Indireta de Fluorescência para Anticorpo , Glutationa/metabolismo , Humanos , Peróxido de Hidrogênio/toxicidade , Cristalino/metabolismo , Oxidantes/toxicidade , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Superóxido Dismutase/metabolismo , Transfecção , Resposta a Proteínas não Dobradas/fisiologia , eIF-2 Quinase/metabolismoRESUMO
The authors describe a fluorometric method for the quantitation of nucleic acids by combining (a) cycled strand displacement amplification, (b) the unique features of the DNA probe SYBR Green, and (c) polydopamine nanotubes. SYBR Green undergoes strong fluorescence enhancement upon intercalation into double-stranded DNA (dsDNA). The polydopamine nanotubes selectively adsorb single-stranded DNA (ssDNA) and molecular beacons. In the absence of target DNA, the molecular beacon, primer and SYBR Green are adsorbed on the surface of polydopamine nanotubes. This results in quenching of the fluorescence of SYBR Green, typically measured at excitation/emission wavelengths of 488/518 nm. Upon addition of analyte (target DNA) and polymerase, the stem of the molecular beacon is opened so that it can bind to the primer. This triggers target strand displacement polymerization, during which dsDNA is synthesized. The hybridized target is then displaced due to the strand displacement activity of the polymerase. The displaced target hybridizes with another molecular beacon. This triggers the next round of polymerization. Consequently, a large amount of dsDNA is formed which is detected by addition of SYBR Green. Thus, sensitive and selective fluorometric detection is realized. The fluorescent sensing strategy shows very good analytical performances towards DNA detection, such as a wide linear range from 0.05 to 25 nM with a low limit of detection of 20 pM. Graphical abstract Schematic of a fluorometric strategy for highly sensitive and selective determination of nucleic acids by combining strand displacement amplification and the unique features of SYBR Green I (SG) and polydopamine nanotubes.
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Fluorometria/métodos , Ácidos Nucleicos/análise , Benzotiazóis , Sondas de DNA/química , DNA de Cadeia Simples , Diaminas , Fluorometria/normas , Indóis , Nanotubos/química , Técnicas de Amplificação de Ácido Nucleico/métodos , Compostos Orgânicos , Polimerização , Polímeros , QuinolinasRESUMO
This paper reports on a colorimetric assay for H2O2 and glucose. It is based on the use of human serum albumin-templated MnO2 nanosheets that possess oxidase-like activity. They are capable of oxidizing 3,3',5,5'-tetramethylbenzidine (TMB) with oxygen to give a blue product (oxTMB) with an absorbance maximum at 652 nm. When H2O2 is introduced, the MnO2 nanosheets are reduced to Mn(II) ions, and this inhibits the formation of oxTMB. Based on these findings, a colorimetric assay was established for H2O2 that has a 0.56 µM detection limit. If glucose is oxidized by glucose oxidase under formation of H2O2, the nanosheets can be used to quantify H2O2 and thereby to sense glucose. Response is linear in the 0.5 µM to 50 µM glucose concentration range, and the detection limit is 0.32 µM. The method was applied to the determination of glucose in spiked serum samples and gave satisficatory results. Graphical abstract Human serum albumin (HSA) is used as a template for the synthesis of MnO2 nanosheet. These possess oxidase mimicking activity. H2O2 can reduce the nanosheets. The effect is exploited in colorimetric assays for H2O2 and glucose using tetramethylbenzidine (TMB) as a chromogenic substrate.
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Técnicas Biossensoriais/métodos , Glicemia/análise , Colorimetria/métodos , Peróxido de Hidrogênio/análise , Compostos de Manganês/química , Nanoestruturas/química , Óxidos/química , Albumina Sérica Humana/química , Benzidinas/química , Materiais Biomiméticos/química , Humanos , Limite de Detecção , Oxirredução , Oxirredutases/químicaRESUMO
PURPOSE: To investigate the association between the 8-oxoguanine DNA glycosylase (OGG1) gene Ser326Cys (rs1052133) polymorphism and age-related cataract (ARC). METHODS: MEDLINE and EMBASE were searched to identify potential studies published before May 19, 2017, investigating the association between the OGG1 gene Ser326Cys polymorphism and ARC risk. The quality of eligible studies was assessed using the Newcastle-Ottawa Scale tool. The association between the OGG1 gene Ser326Cys polymorphism and ARC was analyzed using meta-analysis. Publication bias and sensitivity analyses were also performed. RESULTS: Six studies were included in this systematic review, and five of these studies with Hardy-Weinberg equilibrium were included in a meta-analysis. The sample size of the meta-analysis was 3716, including 1831 patients with cataract and 1885 controls. Odds ratios (ORs) were 0.67 (95% confidence interval (CI) 0.52-0.85), 0.90 (95% CI 0.54-1.51), 0.52 (95% CI 0.32-0.85) and 0.72 (95% CI 0.56-0.92) for recessive, dominant, additive and allele contrast models, respectively. Sensitivity analysis indicated that the results of the meta-analysis were robust. No publication bias was observed. CONCLUSIONS: The OGG1 gene Ser326Cys polymorphism was associated with ARC risk.
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Catarata/genética , DNA Glicosilases/genética , Predisposição Genética para Doença , Guanina/análogos & derivados , Polimorfismo Genético , Alelos , Catarata/metabolismo , DNA Glicosilases/metabolismo , Guanina/metabolismo , HumanosRESUMO
Taxanes, mainly group paclitaxel and docetaxel, are amongst the most promising anticancer agents that are widely used for a variety of tumor types. It is a great challenge to gain a quick overview of the molecular mechanisms of taxanes, owning to the massive amounts of data have been produced. Network pharmacology will be a powerful tool to uncover the drug-targets network of taxanes. In this study, drug-targets network of paclitaxel and docetaxel were constructed via STITCH by database mining, and its topological parameters and important nodes were analyzed. All will provide a systematic understanding for molecular mechanisms of pacltaxel and docetaxel in a quick and visual way.
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Mineração de Dados/métodos , Docetaxel/farmacologia , Paclitaxel/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP , Antineoplásicos Fitogênicos/farmacologia , Biologia Computacional/métodos , Citocromo P-450 CYP2C8 , Bases de Dados Factuais , Receptores ErbB , Humanos , Terapia de Alvo Molecular/métodos , Mapeamento de Interação de Proteínas/métodos , Software , Taxoides/farmacologiaRESUMO
BACKGROUND Diabetic retinopathy (DR) is one of the most common and serious complications of diabetes mellitus (DM). The autophagy-lysosome pathway (ALP) is one of the main intracellular self-digestive degradation systems. Lysosomal impairment and autophagic dysfunction are early events in the pathogenesis of DR, suggesting autophagy might be a novel therapeutic strategy for DR treatment. MATERIAL AND METHODS In our study, we screened a differentially expressed miRNA, miR-1273g-3p, in streptozotocin (STZ)-injected DR rat retinal pigment epithelial (RPE) cells. miR-1273g-3p inhibitor and mimic were employed to treat RPE cells to assess the role of miR-1273g-3p. QRT-PCR and Western blot analysis were performed to examine the function of miR-1273g-3p on ALP-related and DR-related proteins. RESULTS miR-1273g-3p was highly expressed in STZ-induced DM RPE cells. miR-1273g-3p mimic promoted the expression of DR-related MMP-2, MMP-9, and TNF-α proteins, and ALP-related LC3, cathepsin B, and cathepsin L factors, but miR-1273g-3p inhibitor suppressed the levels of these factors. CONCLUSIONS miR-1273g-3p is involved in the progression of DR by modulating the autophagy-lysosome pathway. These findings provided new evidence of the close relationship between DR and ALP, and reveal a new target for DR therapy.
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Retinopatia Diabética/genética , MicroRNAs/metabolismo , Animais , Autofagia/fisiologia , Linhagem Celular , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Lisossomos/fisiologia , MicroRNAs/genética , Ratos , Transdução de Sinais/genéticaRESUMO
A large-scale meta-analysis of 14 genome-wide association studies has identified and replicated a series of susceptibility polymorphisms for coronary artery disease (CAD) in European ancestry populations, but evidences for the associations of these loci with CAD in other ethnicities remain lacking. Herein we investigated the associations between ten (rs579459, rs12413409, rs964184, rs4773144, rs2895811, rs3825807, rs216172, rs12936587, rs46522 and rs3798220) of these loci and CAD in Southern Han Chinese (CHS). Genotyping was performed in 1716 CAD patients and 1572 controls using mass spectrography. Both allelic and genotypic associations of rs964184, rs2895811 and rs3798220 with CAD were significant, regardless of adjustment for covariates of gender, age, hypertension, type 2 diabetes, blood lipid profiles and smoking. Significant association of rs12413409 was initially not observed, but after the adjustment for the covariates, both allelic and genotypic associations were identified as significant. Neither allelic nor genotypic association of the other six polymorphisms with CAD was significant regardless of the adjustment. Our results indicated that four loci of the total 10 were associated with CAD in CHS. Therefore, some of the CAD-related loci in European ancestry populations are indeed susceptibility loci for the risk of CAD in Han Chinese.
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Povo Asiático/genética , Doença da Artéria Coronariana/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Alelos , Estudos de Casos e Controles , China , Doença da Artéria Coronariana/diagnóstico , Frequência do Gene , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Razão de Chances , RiscoRESUMO
Poultry husbandry is a very important aspect of the agricultural economy in China. However, chicks are often susceptible to infectious disease microorganisms, such as bacteria, viruses and parasites, causing large economic losses in recent years. In the present study, we isolated an Acinetobacter baumannii strain, CCGGD201101, from diseased chicks in the Jilin Province of China. Regression analyses of virulence and LD50 tests conducted using healthy chicks confirmed that A. baumannii CCGGD201101, with an LD50 of 1.81 (±0.11) × 10(4) CFU, was more virulent than A. baumannii ATCC17978, with an LD50 of 1.73 (±0.13) × 10(7) CFU. Moreover, TEM examination showed that the pili of A. baumannii CCGGD201101 were different from those of ATCC17978. Antibiotic sensitivity analyses showed that A. baumannii CCGGD201101 was sensitive to rifampicin but resistant to most other antibiotics. These results imply that A. baumannii strain CCGGD201101 had both virulence enhancement and antibiotic resistance characteristics, which are beneficial for A. baumannii survival under adverse conditions and enhance fitness and invasiveness in the host. A. baumannii CCGGD20101, with its high virulence and antimicrobial resistance, may be one of the pathogens causing death of diseased chicks.
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Infecções por Acinetobacter/veterinária , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Doenças das Aves Domésticas/microbiologia , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Acinetobacter baumannii/ultraestrutura , Animais , China , Testes de Sensibilidade Microbiana , Fenótipo , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/mortalidade , VirulênciaRESUMO
A label-free fluorescence assay has been developed for sensitive and selective detection of adenosine triphosphate (ATP) by using poly(thymine) (poly T)-templated copper nanoparticles (CuNPs) as fluorescent indicator. In our design, ATP aptamer was split into two fragments, both of which were elongated with poly T strands that can be utilized as efficient template for the formation of copper nanoparticles through the reduction of copper ions by sodium ascorbate. In the presence of ATP, the two split aptamers could be dragged to form aptamer-ATP aptamer complex, which drew the poly T strands close to each other and induced a remarkable fluorescence enhancement of poly T-templated CuNPs. Thus, an elevated fluorescence enhancement of poly T-templated CuNPs was obtained with the increase in ATP concentration. Under optimized conditions, a good linear range for ATP detection was realized from 100 nM to 100 µM with a detection limit of 10.29 nM. In addition, the application of this biosensing system in complex biological matrix was demonstrated with satisfactory results. This assay provided a simple, label-free, cost-effective, and sensitive platform for the detection of ATP.
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Trifosfato de Adenosina/análise , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Cobre/química , Corantes Fluorescentes/química , Nanopartículas Metálicas/química , Timina/análogos & derivados , Células A549 , Humanos , Limite de Detecção , Espectrometria de Fluorescência/métodosRESUMO
Objective: To optimize the supercritical fluid extraction technology of flavonoids from taxus remainder extracts free of taxoids( TREFT) by response surface methodology( RSM). Methods: By using a central composite design( CCD) in four factors and five levels to optimize the extraction parameters. The effects of extraction time, temperature, pressure and different concentration of ethanol and their interaction on the extraction rate of total flavonoids, amentoflavone, quercetin and ginkgetin which extracted from TREFT by supercritical fluid CO2 were investigated. Results: Under optimal conditions of extraction time for 2. 2 h,and the extraction temperature was 46. 4 â,the extraction pressure was 22. 6 MPa, and 80. 7% ethanol, the index experimental of total flavonoids and monomer compositions was 98. 75. Conclusion: The process of flavonoids extraction from TREFT is stable and feasible, which can provide technical support for the resource utilization of TREFT.